This invention relates to an erase prevention device for use in a recording medium casing to selectively inhibit recording on the recording medium when the recording medium casing is placed in a recorder/player unit.
Case-mounted erasable recording media, such for example as casette tapes, have been employed widely with recorder/player units for repetitive recording of data thereon. In order to protect a user from making a mistake to erase data necessary to be retained, it is the current practice to provide an erase prevention device at one corner of the recording medium casing. Such an erase prevention device includes coaxial holes formed in the recording medium casing for insertion of an inspection probe from a recorder/player unit to inhibit operation of the recorder/player unit in a recording mode when the recording medium casing is placed in the recorder/player unit. The erase prevention device also includes a slider placed in the recording medium casing for sliding movement between two positions. The slider opens the coaxial holes in the first position and closes the coaxial holes in the second position. An aperture is formed in the recording medium casing to provide a visual indication of the slider. The slider closes the aperture and it can be viewed through the aperture when it occupies the first position.
With such a conventional an erase prevention device, however, the user would consider, by mistake, from a glance of one of the coaxial holes that the recording medium is allowed for use in recording data when the slider opens the coaxial holes and that the recording medium is inhibited for use in recording data when the slider closes the coaxial holes.